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General Information => FAQ/Tech Tips/Please Read First => Topic started by: cal on April 21, 2008, 02:15:44 pm
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what marks should i be looking for on the crank, camshaft and pump and what should they be lined up with?
all pics and stats etc welcomed :)
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Unlike a gasser where timing is set lining up some marks on a diesel timing requires a couple of special tools including a dial indicator:
https://vincewaldon.com/2008/10/01/how-to-set-the-injection-pump-timing/
<mods may want to move this thread I'm guessing ??>
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that's great thanks!
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Hi Kenny here in the uk forgive my ignorance but Surely if the engine is already set up properly and all your doing is replacing a belt for a new one you can just lock the pulleys in place and then remove the belt put on new one and new tensioner and done ?
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Kenny, Review Murphy's law. It new goes like you think it should. I never trust the position of locked pulleys as slippage seems to always creep in someplace. Hence, tools, timing and the proverbial hand turning double check.
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Also assuming the tech who was in there before you got everything right is asking for trouble.
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So of you don't have a dial test indicator and your doing it for you first time any advise ?
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So of you don't have a dial test indicator and your doing it for you first time any advise ?
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buy a dial indicator and a Bentley. If it doesn't make sense ask specific questions on what doesn't make sense to you and we'll answer
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So of you don't have a dial test indicator and your doing it for you first time any advise ?
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buy a dial indicator and a Bentley. If it doesn't make sense ask specific questions on what doesn't make sense to you and we'll answer
I second that!
"Mark and pray" is terrible for timing VE diesels, they need to be set up much tighter than that to have the engine run well. The new belt and the old belt won't be exactly the same so trying to transfer things over won't do anything useful.
Timing tool kits can usually be found on eBay or whatever for under $50. Use it once and it's paid for.
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the clearances are much tighter on a diesel engine, and the injection pump timing is measured in fractions of a mm. a difference in tension on the belt can affect the timing, its best to set timing properly, marking or locking and switching stuff around will almost always get it running but not always properly.
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Because the crank drives the pump and cam in only one direction, I do not believe that a change in belt tension affects the timing unless the belt is so tight it bends the injection pump pulley or so loose it jumps time. That said, improper tension causes worse problems than throwing the timing out. Too loose and it can jump time and too tight and it will ruin the injection pump shaft bushings and the intermediate shaft bushings in the engine. The combination of pump rebuild and engine rebuild required to repair a belt that is too tight is very expensive.
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as the motor runs, the belt will stretch, some, this will lengthen belt travel, and hence your timing wont be 'as perfect' as when you set it initially.
I disagree with that. I see it often said that timing belts will stretch but my experience convinces me otherwise. They do not stretch. I have tested the timing before and after a high-mileage belt change and over the course of the next timing belt interval, and the plunger lift did not change at all. Over-tension will cause bushings to fail quickly or in extreme cases can bend the pump bracket, but from what I have seen, the belt length remains consistent.
how much it is off, ive never measured
Until you have actually done the measuring like I have, you are just posting your imagination attempting to contradict the real-world experience of someone who has actually done the measuring...
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You state that changing the tension of the belt changes the timing but you have never measured it doing so. Where do I get off? How dare I quote what you said?
The only time the adjustment of the tensioner changes the 'timing' is when there is slack in the belt between the crank, pump, and cam, or when you have applied so much tension you are damaging parts. If there is slack in the belt then you are not doing the timing procedure correctly. If you are tensioning the belt so much that you are damaging parts you are not doing the procedure correctly.
The belt does not stretch. Changing the tension does not change the timing until you are so far outside the correct tension adjustment that you have worse issues than the timing.
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Fancy terminology? I'm not aware of using any fancy terminology. Are you referring to my proper use of capitalization, contractions and possessive?
I did not come to any conclusion about your procedure. I stated IF/THEN facts about the timing procedure and how to do it correctly. The use of the pronoun 'you' in those if/then statements refers to the collective you and not the specific you. If your procedure does not meet the IF criteria of the if/then statement then you can logically conclude that it does not necessarily include the THEN part of the if/then statement. That's how IF/THEN statements work.
For example take the hypothetical statement, "If you are a magical butterfly then you poop rainbows.". In that statement I am not saying that you DO poop rainbows, unless, of course, you ARE a magical butterfly. Make sense?
If you do the timing procedure correctly there is not any slack between the crank, pump, and cam sprockets when you go to tension the belt. When you tension the belt, it is not possible to remove slack from between the cam, pump, and crank sprockets when there isn't any slack there...
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I have not made any personal or derogatory statements about you. I don't see why you would feel the need to stoop to that. Regardless, I'm glad you have felt amused. It was indeed meant as an absurd and ridiculous hypothetical statement. In that, it was successful. Unfortunately it does not seem to have assisted you in the way it was intended.
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Hooookay that's enough of that.
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